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    <script>
        let user1={
            name:"李四",
            key:Symbol()
        };
        let user2={
            name:"李四",
            key:Symbol()
        };
        let grade={
            [user1.key]:{js:50,css:80},
            [user2.key]:{js:60,css:89}
        };
        console.log(grade[user1.key]);//{js: 50, css: 80}
        console.log(grade[user2.key]);//{js: 60, css: 89} 
        
        
  
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